Method and apparatus for dual tire buffing and handling

ABSTRACT

A dual tire buffing apparatus includes a turntable having a first end and an opposite second end. The turntable is rotatable about a central axis between first and second positions. A first expandable hub is rotatably coupled to the turntable proximate the first end. The first expandable hub is configured to receive a first tire casing. A second expandable hub is rotatably coupled to the turntable proximate the second end. The second expandable hub is configured to receive a second tire casing. A rasp head is positioned to operatively engage the first tire casing on the first expandable hub when the turntable is in the first position to perform a buffing operation on the first tire casing, and to operatively engage the second tire casing on the second expandable hub when the turntable is in the second position to perform a buffing operation on the second tire casing.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.15/633,562, filed Jun. 26, 2017, which is a continuation of U.S. patentapplication Ser. No. 15/355,114, filed Nov. 18, 2016, now U.S. Pat. No.9,688,038, which claims priority to U.S. Provisional Patent ApplicationNo. 62/257,294, filed Nov. 19, 2015, all of which are incorporatedherein by reference in their entireties.

TECHNICAL FIELD

The present disclosure relates generally to the field of retreadingtires, and more specifically to systems and methods for buffing a tirecasing to remove worn tread as part of a retreading process.

BACKGROUND

In general, retreading involves replacing the tread on worn tires.Retreading preserves approximately 90 percent of the material in worntires. The material cost associated with retreading is substantiallyless than the cost of manufacturing a new tire, and retreading permitssignificant recycling.

In a retreading process, a tire casing may be first inspected, which mayinvolve visual and/or machine-based (e.g., shearographic) inspection toidentify non-visible damage and embedded debris (e.g., nails). If thecasing passes the initial inspection, the worn tread may be removedthrough a process referred to as buffing.

Buffing typically may involve removing excess rubber to provide asubstantially evenly-textured crown for receiving a pre-cured treadstrip and to provide a predetermined tire casing profile. Tire casingstypically may include a belt package (a package of steel belts orcables) underlying the road-engaging surface (e.g., the original tread)of the tire. Prior to retreading, the casing may be buffed, generally toa predetermined characteristic crown radius corresponding to the uppercontour of the belt package. The casing may be buffed to leave only apredetermined thickness, e.g., 3/32 of an inch, of material remainingover the top belt. The shoulder of the casing may also be buffed(trimmed) to eliminate or reduce voids or patterns in the shouldercreated by the original tread, and to provide, typically, a relativelycontinuous profile between the casing sidewalls and the crown. A worncasing from each of various models and sizes of new tires has acharacteristic tire casing profile of a particular crown width, crownbuffing radius and shoulder trim angle which may be created as aninitial step in the buffing process.

After being buffed, the tire casing may then be examined for injuries,which may be skived and filled with a repair gum. After completion ofthe skiving process, the buffed surface may be sprayed with tire cementthat provides a tacky surface for application of a suitable layer ofbonding material, such as cushion gum. The cushion gum may be a layer ofuncured rubber material, which optionally may include a low temperaturevulcanizing agent and accelerator. The cushion gum can be placed overthe crown. In some retreading operations, the spray cement can beomitted.

A cured tread strip, typically of a width corresponding to the width ofthe crown of the casing, may then be cut to the length corresponding tothe casing circumference and disposed over the casing crown.Alternatively, continuous replacement treads in the shape of a ring(i.e., ring treads) may be used to retread the buffed casing. A rollerpressing process, commonly referred to as stitching, may be performed onthe assembly to force air from between the tread strip and casing.

After stitching the tire assembly, which includes the tire casing, thecushion gum and the tread, the assembly may be placed within a flexiblerubber envelope. An airtight seal can be created between the envelopeand the bead of the tire casing. The entire envelope, with the tireassembly disposed therein, can be placed within a curing chamber andsubjected to elevated pressure and temperature for a predeterminedperiod of time. The combination of exposure to elevated pressure andtemperature for a duration of time may bind the cushion gum to both thetire casing and the new tire tread.

Buffing in the noted process may be performed by a buffing apparatusincluding a rasp and a tire mounted so that the rasp may come intocontact with the tire's outer surface. An operator may perform aninitial inspection process to analyze the current condition of a tirecasing. The tire casing may then be mounted to the tire hub assembly.For example, the tire hub assembly may include a tire chuck with anexpandable rim for accepting tire casings of various sizes. Afterbuffing has been completed the operator may remove the tire and send itto another location for further processing.

Buffing and skiving processes take approximately 3 minutes per tire. Ofthe 3 minutes, the buffing process takes approximately 2 minutes,loading and unloading take approximately 15 seconds each, and skivingtakes approximately 30 seconds. In addition, the rasp head must come toa complete stop after completing a buffing process, and must berestarted to buff the next tire. When operating at production rate, thiscorresponds to approximately 20 start/stop sequences per hour. Eachstart/stop sequence requires a substantial in-rush of current into therasp motor in order to accelerate the rasp head to bring the rasp headup to operating speed. Energy is also needed to bring the rasp head to astop. The start/stop sequences also stress and ultimately reduce theuseful life of the components of the rasp head, thereby requiringregular maintenance.

SUMMARY

As disclosed herein, an example apparatus includes a turntable having afirst end and an opposite second end. The turntable is rotatable about acentral axis between a first position and a second position. A firstexpandable hub is rotatably coupled to the turntable proximate the firstend. The first expandable hub is configured to receive a first tirecasing. A second expandable hub is rotatably coupled to the turntableproximate the second end. The second expandable hub is configured toreceive a second tire casing. A rasp head is positioned to operativelyengage the first tire casing on the first expandable hub when theturntable is in the first position to perform a buffing operation on thefirst tire casing, and the rasp head is positioned to operatively engagethe second tire casing on the second expandable hub when the turntableis in the second position to perform a buffing operation on the secondtire casing.

As disclosed herein, another example apparatus includes a rasp pedestal.A circular track surrounds the rasp pedestal. A first carrier isoperatively coupled to the track and is movable along the track betweena first position and a second position. The first position is adjacentthe rasp pedestal. A second carrier is operatively coupled to the trackseparated from the first carrier. The second carrier is movable betweenfirst and second positions. The second position is adjacent the rasppedestal. A first expandable hub is rotatably coupled to the firstcarrier. The first expandable hub is configured to receive a first tirecasing. A second expandable hub is rotatably coupled to the secondcarrier. The second expandable hub is configured to receive a secondtire casing. The first expandable hub is positioned for buffing of thefirst tire casing when the turntable is in the first position. Thesecond expandable hub is positioned for buffing of the second tirecasing when the turntable is in the second position.

As disclosed herein, an example method includes permitting a buffingoperation on a first tire casing operatively coupled to a firstexpandable hub. While performing the buffing operation on the first tirecasing, the method includes (1) performing a skiving operation on asecond tire casing operatively coupled to a second expandable hubmounted on the turntable separate from the first expandable hub; (2)unloading the second tire casing from the second expandable hub; (3)loading a third tire casing onto the second expandable hub; and (4)rotating the first expandable hub from a first position to a secondposition for performing a skiving operation while simultaneouslyrotating the second expandable hub from a second position to a firstposition for performing a buffing operation.

The features of the present invention will become apparent to one ofordinary skill in the art upon reading the detailed description, inconjunction with the accompanying drawings, provided herein. Theembodiments provided herein are not intended to limit the invention tosuch embodiments, but instead are provided with the understanding thatchanges and modifications may be made within the scope of the claimedinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a dual tire buffing apparatus, according to anembodiment.

FIG. 2 illustrates the turntable of the dual tire buffing apparatus ofFIG. 1 as partially rotated between the first and second positions.

FIG. 3 illustrates the turntable of the dual tire buffing apparatus ofFIGS. 1 and 2 in the second position.

FIG. 4 is a plan view of a dual tire buffing apparatus, according toanother embodiment.

FIG. 5 illustrates the first and second carriers the dual tire buffingapparatus of FIG. 4 as partially rotated between the first and secondpositions.

FIG. 6 illustrates the first and second carriers of the dual tirebuffing apparatus of FIGS. 4 and 5 in the second position.

FIG. 7 is a plan view of a dual tire buffing apparatus, according toanother embodiment.

FIG. 8 is a flow diagram of a method of simultaneously performingbuffing and skiving operations on tire casings, according to anembodiment.

DETAILED DESCRIPTION

FIG. 1 is a plan view of a dual tire buffing apparatus 100, according toan embodiment. The dual tire buffing apparatus 100 includes a baseassembly 102, a rasp pedestal 104, a rasp pedestal moving assembly 106,fencing 110, an electrical enclosure 112, a pneumatic enclosure 114, andan human-machine interface (HMI) terminal 116. The dual tire buffingapparatus 100 also includes a dual tire hub assembly 108. The dual tirehub assembly 108 of the dual tire buffing apparatus 100 enables multipletire casings to be processed at the same time. As will be appreciated,the dual tire buffing apparatus 100 provides significant time and energysavings.

The rasp pedestal 104 includes a rasp head assembly 118 rotatablycoupled to the rasp pedestal 104. The rasp head assembly 118 can includea rasp head 120 and a texturing device 122. The rasp head 120 isstructured to remove material from the tire casing being buffed. Thetexturing device 122 is structured to impart a desired texture on atleast a portion of the tire casing. In one embodiment, the texturingdevice 122 includes a wire brush. A rasp drive motor (not shown) isstructured to controllably drive the rasp head assembly 118. Morespecifically, the rasp drive motor is structured to rotate a shaft uponwhich one or both of the rasp head 120 and the texturing device 122 maybe mounted.

The rasp pedestal moving assembly 106 is configured to controllably movethe rasp pedestal 104 relative to the dual tire hub assembly 108 alongeach of an X-axis, a Y-axis, and a Z-axis. In some embodiments, the rasppedestal moving assembly 106 may be controlled automatically via acontrol unit (not shown) housed in the electrical enclosure 112. Inother embodiments, the rasp pedestal moving assembly 106 is controlledsemi-automatically or manually by an operator via the HMI terminal 116.

The fencing 110 extends around at least a portion of the rasp pedestal104, the rasp pedestal moving assembly 106, and the dual tire hubassembly 108, so as to prevent objects from unintentionally entering orexiting the operational area of the dual tire buffing apparatus 100. Theelectrical enclosure 112 and the pneumatic enclosure 114, and the HMIterminal 116 may each be positioned external to the fencing 110.

The dual tire buffing apparatus 100 also includes a swing arm 124. Theswing arm 124 is positioned such that the dual tire hub assembly 108 isdisposed intermediate the swing arm 124 and the rasp pedestal 104. Theswing arm 124 includes a secondary buffing and texturing head 126configured to perform secondary buffing and texturizing operations ontire casings. Although not shown in FIG. 1, other embodiments mayinclude material collection systems proximate one or both of the rasppedestal 104 and the swing arm 124 to collect material removed from tirecasings.

The dual tire hub assembly 108 of the dual tire buffing apparatus 100also includes first and second expandable hubs 128, 130 operativelycoupled to a turntable 132. The turntable 132 is rotatable between firstand second positions. In each position, a buffing operation can beperformed on one tire casing loaded on one of the first and secondexpandable hubs 128, 130, while skiving, unloading, and loadingoperations are performed on other tire casings on the other of the firstand second expandable hubs 128, 130. Thus, a single operator can operatethe dual tire buffing apparatus 100 to buff a first tire casing whileskiving and unloading a second tire casing and subsequently loading athird tire casing. In many situations, skiving, unloading, and loadingoperations may be performed in less time than it takes to complete thebuffing operation. Accordingly, the dual tire buffing apparatus 100enables significant time savings over prior tire buffing systems. Thedual tire buffing apparatus 100 configuration also enables the rasp headto be continuously rotated rather than being stopped between eachbuffing process. Accordingly, the dual tire buffing apparatus 100 alsoprovides energy savings over prior tire buffing systems, while furtherreducing wear and tear on the rasp head.

As shown in FIG. 1, the turntable 132 includes a turntable hub 134,which is rotatable about a central axis 136. The turntable also includesa first arm 138 extending from the turntable hub 134 to a first end 140,and a second arm 142 extending from the turntable hub 134 to a secondend 144 opposite the first end 140. In some embodiments, the first andsecond arms 138, 142 are defined by a single elongate member. The firstand second arms 138, 142 are rigidly coupled to the turntable hub 134such that rotation of the turntable hub 134 causes correspondingrotation of the first and second arms 138, 142 of the turntable 132, andtherefore, of the first and second expandable hubs 128, 130.

The turntable 132 is shown in FIG. 1 in the first position. In the firstposition, the first expandable hub 128 is positioned proximate the rasppedestal 104. In the first position, the rasp head 120 is configured toengage a first tire casing (not shown) on the first expandable hub 128to perform a buffing operation on the first tire casing. In addition,the second expandable hub 130 is positioned proximate the swing arm 124so as to perform skiving and unloading operations on a second tirecasing (not shown) on the second expandable hub 130, and to subsequentlyload a third tire casing (not shown) onto the second expandable hub 130.

FIG. 2 illustrates the turntable 132 of FIG. 1 as partially rotatedbetween the first and second positions. More specifically, the turntable132 is being rotated counter-clockwise about the central axis 136 sothat the first expandable hub 128 moves towards the swing arm 124, andthe second expandable hub 130 moves towards the rasp pedestal 104. Inother embodiments, the turntable 132 rotates clockwise. In someembodiments, the turntable 132 is configured for 360 degree rotation. Inother embodiments, the turntable 132 is configured for 180 degreerotation. In one embodiment, rotation between the first and secondpositions may take about six seconds. In another embodiment, rotationbetween the first and second positions may take less than ten seconds.

FIG. 3 illustrates the turntable 132 of FIGS. 1 and 2 in the secondposition. As illustrated in FIG. 3, the first expandable hub 128 ispositioned proximate the swing arm 124, and the second expandable hub130 is positioned proximate the rasp pedestal 104. It can be seen thatthe position of the first and second expandable hubs 128, 130 isswitched between the first and second positions.

With reference to FIGS. 1-3, various arrangements of the dual tirebuffing apparatus 100 will be described in reference to first, second,and third tire casings. It should be understood that the first tirecasing is operatively coupled to the first expandable hub 128. Thesecond tire casing is operatively coupled to the second expandable hub130. The second tire casing should be understood to have alreadycompleted a buffing process by the rasp head 120. The third tire casingshould be understood as being next in queue to be processed after thefirst and second tire casings.

The rasp head 120 is positioned to operatively engage the first tirecasing on the first expandable hub 128 when the turntable 132 is in thefirst position to perform a buffing operation on the first tire casing,and to operatively engage the second tire casing on the secondexpandable hub 130 when the turntable 132 is in the second position toperform a buffing operation on the second tire casing. The rasp head 120is rotated relative to the rasp pedestal 104 to perform the buffingoperation. In some embodiments, the rasp head is continuously rotatedwhile performing buffing operations on a plurality of tire casings.

The first expandable hub 128 is positioned for skiving of the first tirecasing when the turntable 132 is in the second position (FIG. 3), andthe second expandable hub is positioned for skiving of the second tirecasing when the turntable 132 is in the first position (FIG. 1). Thefirst expandable hub 128 is configured to accept and release the firsttire casing when the turntable 132 is in the second position (FIG. 3).The second expandable hub is configured to accept and release the secondtire casing when the turntable 132 is in the first position (FIG. 1).

The swing arm 124 is positioned to operatively engage the second tirecasing on the second expandable hub 130 when the turntable 132 is in thefirst position (FIG. 1), and to operatively engage the first tire casingon the first expandable hub 128 when the turntable 132 is in the secondposition (FIG. 3). The swing arm 124 may be configured to impart apredetermined texture upon the shoulders of each of the first and secondtire casings.

FIG. 4 is a plan view of a dual tire buffing apparatus 400, according toanother embodiment. As shown in FIG. 4, the dual tire buffing apparatus400 includes a base assembly 402, a rasp pedestal 404 and rasp pedestalmoving assembly 406. The rasp pedestal moving assembly 406 is mounted tothe base assembly 402, and the rasp pedestal 404 is mounted to the rasppedestal moving assembly 406. The rasp pedestal 404 includes a rasp head408 rotatably coupled to the rasp pedestal 404.

The dual tire buffing apparatus 400 also includes a circular track 410surrounding the rasp pedestal 404 and the rasp pedestal moving assembly406. First and second carriers 412, 414 are operatively coupled to thetrack 410 on opposite sides thereof. The first and second carriers 412,414 are movable on the track 410 between first and second positions. Inthe first position, the first carrier 412 is adjacent the rasp pedestal404. In the second position, the second carrier 414 is adjacent the rasppedestal 404.

A first hub assembly 416 including a first expandable hub 418 is mountedto the first carrier 412, such that the first expandable hub 418 isrotatable relative to the first carrier 412. The first expandable hub418 is configured to receive a first tire casing 420. A second hubassembly 422 including a second expandable hub 424 is mounted to thesecond carrier 414, such that the second expandable hub 424 is rotatablerelative to the second carrier 414. The second expandable hub 424 isconfigured to receive a second tire casing 426.

The dual tire buffing apparatus 400 also includes a swing arm 428. Theswing arm 428 is positioned outside of the track 410 opposite the rasppedestal 404. The swing arm 428 includes a secondary buffing andtexturing head 430 configured to perform secondary buffing andtexturizing operations on tire casings.

The dual tire buffing apparatus 400 may also include fencing 432 atleast partially surrounding the rasp pedestal 404 so as to preventobjects from objects from unintentionally entering or exiting theoperational area proximate the rasp pedestal 404. According to anembodiment, as illustrated in FIG. 4, the fencing 432 may be disposedinside of the track 410 such that the track 410 surrounds the fencing432. The swing arm 428, as well as electrical and pneumatic enclosures434, 436, may be disposed external to the track 410.

Similar to the dual tire buffing apparatus 100 of FIGS. 1-3, the dualtire buffing apparatus 400 of FIG. 4 is configured to perform a buffingoperation on one tire casing loaded on one of the first and secondexpandable hubs 418, 424, while simultaneously performing skiving,unloading, and loading operations on other tire casings on the other ofthe first and second expandable hubs 418, 424. For example, the dualtire buffing apparatus 400 is shown in FIG. 4 in the first position. Inthe first position, the first carrier 412 is positioned proximate therasp pedestal 404 and the second carrier 414 is positioned proximate theswing arm 428. Accordingly, in the first position, the first tire casing420 mounted to the first expandable hub 418 is positioned to undergo abuffing operation, and the second tire casing 426 mounted to the secondexpandable hub 424 is positioned to undergo a skiving operation and tobe unloaded. A third tire casing (not shown) may subsequently be loadedand mounted onto the second expandable hub 424.

FIG. 5 illustrates the dual tire buffing apparatus 400 of FIG. 4, withthe first and second carriers 412, 414 of FIG. 4 shown as partiallyrotated between the first and second positions. More specifically, thefirst and second carriers 412, 414 are being rotated clockwise along thetrack 410 so that the first expandable hub 418 moves towards the swingarm 428, and the second expandable hub 424 moves towards the rasppedestal 404. In other embodiments, the first and second carriers 412,414 rotate counter-clockwise. In some embodiments, the first and secondcarriers 412, 414 are configured for 360 degree rotation around thetrack 410. In other embodiments, the first and second carriers 412, 414are configured for 180 degree rotation along the track 410. In oneembodiment, rotation between the first and second positions takes sixseconds. In another embodiment, rotation between the first and secondpositions takes less than ten seconds.

FIG. 6 illustrates the first and second carriers 412, 414 of FIGS. 4 and5 in the second position. As illustrated in FIG. 6, the first expandablehub 418 is positioned proximate the swing arm 428, and the secondexpandable hub 424 is positioned proximate the rasp pedestal 404. It canbe seen that the position of the first and second expandable hubs 418,424 is switched between the first and second positions.

FIG. 7 is a plan view of a dual tire buffing apparatus 700, according toanother embodiment. As shown in FIG. 7, the dual tire buffing apparatus700 is generally similar to the dual tire buffing apparatus 400 of FIGS.4-6. However, the dual tire buffing apparatus 700 includes an electricalenclosure 702, a pneumatic enclosure 704, an HMI terminal 706, and aswing arm 708, each positioned inside of a track 710. In other words,the track 710 surrounds each of the electrical enclosure 702, thepneumatic enclosure 704, the HMI terminal 706, and the swing arm 708.

In another embodiment, instead of having two tire drives or hubs thatrotate relative to the rasp pedestal, an example apparatus includes twostationary tire drives, and a rasp pedestal rotates relative to the tiredrives. In this embodiment, an operator must walk between each tiredrive to skive an unload a finished tire casing, and to load the nexttire casing. In a further embodiment, tire hubs are transmittedvertically (e.g., between floors of a building) instead of rotationallyon a single floor.

In other embodiments, additional carriers may be mounted to increase thenumber of tires in process. For example, in FIG. 4, additional carriersmay be added half-way between the shown carriers so that carriers wouldbe present at 0 degrees (first carrier 412), 90 degrees, 180 degrees(second carrier 414), and 270 degrees around the periphery.

FIG. 8 is a flow diagram of a method 800 of simultaneously performingbuffing and skiving operations on tire casings, according to anembodiment. For example, the method 800 may be performed in connectionwith any of the dual tire buffing apparatus 100, 400, or 700 of FIGS.1-7. However, it should be understood that the method 800 is not limitedto these example embodiments.

At step 802, a buffing operation is performed on a first tire casingoperatively coupled to a first expandable hub. The buffing operation maybe performed by controllably engaging a rasp head with the first tirecasing and moving the rasp head along a predetermined path relative tothe first tire casing so as to remove worn tread from the first tirecasing. The first tire casing is buffed to achieve a desired tire casingprofile. The buffing operation may also include imparting a desiredtexture on at least a portion of the tire casing.

Steps 804-808 are performed simultaneous to step 802. At 804, a skivingoperation is performed on a second tire casing operatively coupled to asecond expandable hub. The second tire casing has been buffed prior toundergoing the skiving operation at 804. Skiving can involve inspectingthe buffed tire casing for injuries, which are skived and filled with arepair gum. The skiving process at 804 may also include performing asecondary buffing and texturizing operation on the second tire casing.

At 806, the second tire casing is unloaded from the second expandablehub upon completion of the skiving operation at 804. Upon unloading thesecond tire casing from the second expandable hub, the remainingretreading processes may be performed on the second tire casing so as toprovide a complete retreaded tire.

At 808, a third tire casing is loaded onto the second expandable hub.The third tire casing is in queue to be buffed and skived subsequent tothe first and second tire casings.

At 810, upon completing steps 802, as well as steps 804-808, a turntableof the dual tire buffing assembly may be rotated so as to move the dialtire buffing assembly from a first position to a second position. Uponthe turntable being rotated to the second position, a buffing process isperformed on the third tire casing, and skiving and unloading processesare performed on the first tire casing.

The use of the terms “a” and “an” and “the” and similar referents in thecontext of describing the invention (especially in the context of thefollowing claims) are to be construed to cover both the singular and theplural, unless otherwise indicated herein or clearly contradicted bycontext. Recitation of ranges of values herein are merely intended toserve as a shorthand method of referring individually to each separatevalue falling within the range, unless otherwise indicated herein, andeach separate value is incorporated into the specification as if it wereindividually recited herein. All methods described herein can beperformed in any suitable order unless otherwise indicated herein orotherwise clearly contradicted by context. The use of any and allexamples, or exemplary language (e.g., “such as”) provided herein, isintended merely to better illuminate the invention and does not pose alimitation on the scope of the invention unless otherwise indicated.

While the invention is described herein in connection with certainpreferred embodiments, there is no intent to limit the present inventionto those embodiments. On the contrary, it is recognized that variouschanges and modifications to the described embodiments will be apparentto those skilled in the art upon reading the foregoing description, andthat such changes and modifications may be made without departing fromthe spirit and scope of the present invention. The inventors expectskilled artisans to employ such variations as appropriate, and theinventors intend for the invention to be practiced otherwise than asspecifically described herein. Accordingly, the intent is to cover allalternatives, modifications, and equivalents included within the spiritand scope of the invention. Moreover, any combination of theabove-described elements in all possible variations thereof isencompassed by the invention unless otherwise indicated herein orotherwise clearly contradicted by context.

What is claimed is:
 1. An apparatus, comprising: a base comprising afirst arm extending from a central axis toward a first base end and asecond arm extending from the central axis toward a second base end, thefirst base end opposite the second base end, wherein the base isrotatable about the central axis between a first position and a secondposition; a first hub coupled to the base proximate the first arm, thefirst hub configured to receive a first tire casing, the first hubcoupled to the first arm such that a diameter of the first tire casingis substantially perpendicular to the first arm; a second hub coupled tothe base proximate the second arm, the second hub configured to receivea second tire casing, the second hub coupled to the second arm such thata diameter of the second tire casing is substantially perpendicular tothe second arm; a buffing member positioned to operatively engage thefirst tire casing on the first expandable hub when the base is in thefirst position to perform a first buffing operation on the first tirecasing, the buffing member positioned to operatively engage the secondtire casing on the second expandable hub when the base is in the secondposition to perform a second buffing operation on the second tirecasing, wherein the buffing member is configured to remove worn tread.2. The apparatus of claim 1, wherein the buffing member comprises a rasphead positioned to operatively engage the first tire casing on the firstexpandable hub when the base is in the first position to perform a firstbuffing operation on the first tire casing, the rasp head positioned tooperatively engage the second tire casing on the second expandable hubwhen the base is in the second position to perform a second buffingoperation on the second tire casing.
 3. The apparatus of claim 2,wherein the rasp head is rotatably coupled to a rasp base, wherein therasp head is rotated relative to the rasp base to perform the first andsecond buffing operations.
 4. The apparatus of claim 2, wherein the baseis configured to rotate clockwise about the central axis such that thefirst expandable hub moves toward second expandable hub and the secondexpandable hub moves toward the rasp head after completion of the firstbuffing operation.
 5. The apparatus of claim 4, wherein the base isconfigured for 360 degree rotation, such that the second expandable hubmoves toward first expandable hub and the first expandable hub movestoward the rasp head after completion of the second buffing operation.6. The apparatus of claim 2, wherein the rasp head is a hanging rasphead.
 7. The apparatus of claim 1, wherein the first arm and the secondarm are colinear.
 8. The apparatus of claim 7, wherein the base isrotatable about the central axis between a first position and a secondposition.
 9. The apparatus of claim 8, further comprising a rasp headpositioned to operatively engage the first tire casing on the firstexpandable hub when the base is in the first position to perform a firstbuffing operation on the first tire casing, the rasp head positioned tooperatively engage the second tire casing on the second expandable hubwhen the base is in the second position to perform a second buffingoperation on the second tire casing.
 10. The apparatus of claim 9,wherein the base is configured to rotate clockwise about the centralaxis such that the first expandable hub moves toward second expandablehub and the second expandable hub moves toward the rasp head aftercompletion of the first buffing operation.
 11. The apparatus of claim10, wherein the base is configured for 360 degree rotation, such thatthe second expandable hub moves toward first expandable hub and thefirst expandable hub moves toward the rasp head after completion of thesecond buffing operation.
 12. The apparatus of claim 11, wherein therasp head is a vertical buffing head.
 13. The apparatus of claim 9,wherein the rasp head is a hanging rasp head.
 14. The apparatus of claim8, comprising a buffing member positioned to operatively engage thefirst tire casing on the first expandable hub when the base is in thefirst position to perform a first buffing operation on the first tirecasing, the buffing member positioned to operatively engage the secondtire casing on the second expandable hub when the base is in the secondposition to perform a second buffing operation on the second tirecasing, wherein the buffing member is configured to remove worn tread.15. An apparatus, comprising: a base having a first end and a second endopposite the first end, the base rotatable about a central axis, thecentral axis disposed between the first end and the second end; a firsthub coupled to the base proximate the first end, the first hubconfigured to receive a first tire casing; and a second hub coupled tothe base proximate the second end, the second hub configured to receivea second tire casing.
 16. The apparatus of claim 15, wherein the basecomprises a turntable rotatable about the central axis between a firstposition and a second position.
 17. The apparatus of claim 16, whereinthe turntable is configured for 360 degree rotation.
 18. A method,comprising: performing a first buffing operation on a first tire casingoperatively coupled to a first hub, wherein simultaneous to performingthe first buffing operation on the first tire casing, a second tirecasing operatively coupled to a second hub is accessible, the second hubcoupled to a base proximate a second end, the first hub coupled to thebase proximate a first end, wherein first end of the base is oppositethe second end of the base about a central axis, the base rotatableabout the central axis; rotating the base about the central axis; andperforming a second buffing operation on a second tire casingoperatively coupled to the second hub, wherein simultaneous toperforming the second buffing operation on the second tire casing, thefirst tire casing operatively coupled to the first hub is accessible.19. The method of claim 18, wherein a rasp head is positioned tooperatively engage the first tire casing on the first hub to perform afirst buffing operation on the first tire casing, and wherein rotatingthe base about the central axis comprises rotating the base about thecentral axis such that the first hub moves toward second hub and thesecond hub moves toward the rasp head.
 20. The method of claim 19,further comprising: loading a third tire casing on the first hub; androtating the base about the central axis such that the buffed secondtire casing on the second hub moves toward first hub and the third tirecasing on the first hub moves toward the rasp head.